Direct-acting-solenoid resistance-regulator for train-lighting systems.



v P. KENNEDY. I 'DIRECT ACTING SOLENOID RESISTANCE REGULATOR FOR TRAIN LIGHTING SYSTEMS.

APPLICATION FILED IULY 6.1912.

1,179,530. Patented Apr. 18,1916.

' 2 SHEETS-SHEET 1. Z!

WITNESSES: NVENTOR I film/ aw i/ 7 ATTORNEYS F KENNEDY.

DIRECT ACTING SOLENOID RESISTANCE REGULATOR. FOR mm ucurmc SYSTEMS. APPLICATION FILED IULY 6.1912.

1,179,530. Patented Apr. 18, 1916.

2 SHEETS-SHEET 2- llHii mam gmirfih mlh lH llm INVENTOR UNITED STATES. PATENT OFFICE,

PATRICK KENNEDY, OF BROOKLYN, NEW YORK.

DIRECT-ACTING-SOLENOID RESISTANCE-REGULATOR FOR TRAIN-LIGHTING SYSTEMS.

Specification of Letters Eatent. Patented Apr. 18, 1916.

Application filed July 5, 1912. Serial No. 207,9233.

To all whom it may concern: i

Be it known that I, PATRICK KEN EDY, a citizen of the United States, residing at 177 Bedford avenue, Brooklyn, county of Kings,

State of New York, have invented certain new and useful Improvements in Direct- Acting-Solenoid Resistance-Regulators for Train-Lighting Systems; and I" do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same! The object of the invention is to produce,-

for train-lighting and like systems in which the resistance has to be varied. by 'small in- I crements over a wide 'range, a solenoid resistance regulator havlng such construction that the limited power of 'a small compact fsoleno id is effective, without the interposiance-varying movementsof the desired am tion of any intermediate or auxiliarymechanism, to lmpart to the contact-arm resistplitude, and with freedom from circuit interruptions or sparks due to the jar which is necessarily incide t to the contemplated use, or due to poor co tact arising from the collection of dirt'or dust on the contact surfaces, or to improper order of separation of i bon pile, a much more even gradation of resistance variation is obtained and the auxiliary tapper employed with a carbon pile isdispensed with; While it differs from the known regulators in which the contact sur- 1 face slides over the resistance terminals in that, by the use of a rolling contact surface constructedand actuated in the manner described, it becomes possible to employ a. sole-.

noid directly, connected to the contact-arm, eliminating all intermediate mechanism with its attendant expense, uncertainty of operation,'occupat-ion of space and difiiculty of re- In. the accompanying drawings, which illus rate the"preferred embodiment of the;

invention, Figure is a central vertical section on'the line 1 1 of Fig. 2; F1g. 21s a "topplan view partly broken away; Fig. 3' is a View of 'rthe contact-arm and connections viewed from the right in Fig. 1, and shows also in outline two of the resistance grids; Fig. 4 is a detail view, showing one of the blades and one-of the spacerstrips of which the contact-arm is built up, and, Fig. 5 is a section on the line 55 of Fig. 2, showing the manner in which spring pressure is applied to the contact-arm.

The solenoid proper is of ordinary constructlon, consisting of an outer shell a of iron, closed at one end by a cap b,and at the other end by an annular plate 0 of iron, throi gh which projects an iron'tube' or core (Z. he solenoid has an exciting winding,in-

dicated at a, the arrangement of which will depend upon the use to which the regulator is to be applied. That isto say, in a lamp regulator the exciting winding will be in a shunt across the lamp circuit,while in the case of a generator field resistance regulator the exciting winding will be made up ofone ,or more windings connected in the circuit in any desired manner. l Vhatever arrangement of exciting winding may characterize the use of the solenoid, the binding posts I) are provided for making the necessary connection. The stem 0' of'the movable core d passes loosely through the fixed core member (Z and is guided by a lubricating bushing e of graphite or the like. The

movable core cl is preferably incased within a brass tube 6 and carries at the lower end a piston f, preferably of graphite or the like,

and moving-1n apiston chamber f in the lower end of the solenoid casing. Communication is established from one side of the piston f to the other by a by-pass 9 controlled by a valve screw 9'. The piston f acts as a dash-pot and performs. the im-' portant function of steadying the movement of the contact-arm and preventing oscillations thereof upon sudden variations in the condition of the controlled electrical circuit as well as vibrations due to the mechanical jar which is incident to train lighting servcharacter of the clash-pot action may be regulated, and because of the fact that the bypass has no opening to the exterior, through which dust or dirt might enter, the

piston chamber may contain a lubricating -fluid which will not become thickened with dirt.

The resistance is preferably made up of a number of compactly arranged resistance grids h suitably connected in series and preferably arranged in two rows, so that ice. By means of the controlled by-pass, the

maintaining the small gradations.

the resistance'varying effect of a movement 7 -of the contact-arm may be increased. In the arrangement shown, the twoflsets of resistance grids are arranged in staggered relation to one'another so that the grids of the two sets are cutinto and out ofcircuit seriazfim, whereby this increase of resistance varying effect is accomplished whille T e grids are securely held in a suitable support, as shown, and are exposed at the upper end to form contact surfaces, the eX- posed portions oeing preferably composed of a metal which has better -conductivity than the material of the grids. It is important, for the; best regulation, that the necessary movement of the contactarm,

while the individual sections should be of such a number, and so brought into and out of the 'circuit, that. the resistance changes will beby small increments which will. not cause the lamps to flicker.v No at tempt has been made inthe drawings to show the proper numloerof resistance elements employed, and it may be Well to say that in practice there is contemplated theemployment of, say, 120 individual grids in a field regulator of standard construction, whereas a less number, say about 90,

is ordinarily suflicient for a lampregulator. 4O

A further important element of the combination is the contact-arm i with thecontact-making elements of: the peculiar con-' struction illustrated in Figs. 1, 3 and 4. It

has 7 been found essential, if freedom of movement is to be combined with firm con-'- tact, that the contact surfaces should be pressed together as by a spr ng, and-it has further been discovered that it is impossible to thus establish the close and uniform con-' tact which is essential toprevent sparking as the contact-arm moves over the -compactly-arranged contact terminals, if plane surfaces are employed. Even small particles of dust on the surfaces will give rise to sparks, which so pit and roughen the surfaces that ina short time the apparatus be comes inoperative 'for anyuseful purpose.

. On the other hand, 'theuse of thin plates of conducting material bound together. to form a brush, and adapted upon yielding under j v the pressure .to; make a lateral wiping con 7 tact, as commonly employed in -c1rcu1t breakers, fonxample, is open to'the de-' feet, when applied to :thepresent-purpose,

that the lateral "wiping inovement' of and falls.

. I. I I ,7 i l I l I -individual plates so increases the area of the surface in contact that it becomes impossible.

to introduce and remove sem'atz'm the compactly-ar ifanged res1stance elements, the wiping action giving rise to an improper order of introduction and. removal of the elements, .and consequent sparking. These difiiculties have been overcome in. the present construction, in which the two contact portions orbrushes of the contact-arm are builtup'of a series of thin metal plates .71,

separated by spacing strips 2' and em bracecl'by jaw-like portions of the contactarm, ,as shown in Fig. 3. The plates 2" are deformed laterally, and preferably wealv ened, at aregion. between the contact edges and the portion embraced by the jaws of the arm, so that under pressure the individual plates will yield sor'newhat, and yet the contact edges of the plates are at all times normal to the surfaces of the resistance terminals. With'this construction, the proper introduction and'removal of the resistance elements s assured, since there is no lateral wiping action, and yet each plate 2'", being capable of yielding individually, acts, un-

der the pressure applied, as a knife edge,

and cuts its own way to a good contact independently of all the other contact plates or blades.

The preferred manner of applying the spring pressure is'illustrated in Figs. 1 and 5 and comprises a blade spring A: fastened to the frame of the regulator and engagin'g a stirrup la de ending from the connecting portion of the c'ontactnrm 2'. In this man-' ner thepressure is applied at thecenter of,

the contact-arm and is evenly distributed It-will v to efiect the best possible "contact.

be-seen that the edges of the contact-plates 1 are curved in any suitable arc orl'combi-i q nation of arcs to obtain the proper shifting of the point of contact as the solenoid rises In. order to obtain the close regulation under all the varying conditions incident" tp train lighting service, it is important,

geven with the arrangement of grids and contact-arm. thus described, to extend 'the accurate .movement of the solenoid over as.

wide a range as practically possible, and to this end it greatly improves the apparatus solenoid, due to a given change in electrical conditions, is equalized over the desired if the variation inmechanic'al pull of the V I range of movement of the solenoid. This may be, andcommonlyis, partially effected by making, the surface, at the air ga of. the

fixed and movablecores d and d, o conical shape; but in order to get the best results under the difficult cpnditions of service contemplated it is desirable to further bring about such equalization of pull. To this end, there has been provided a spring acting .upon-the solenoid'plunger in such manner ..Inoid. Such a construction is shown in Fig.

1, in which-the spring Z presses downwardly upon an upward extension of the core it having been found that .the .best result is arm made up of plates making yielding rolling contact wlth obtained .when the point of application of spring pressure is on, the axis of the plunger. The effect of the spring is made to correspond to the varying effect of the magnetic pull by supporting the spring beneath a cam Z which is carefully shaped to give the desired increase of spring pressure as the pull increases. The shape of the cam can be determined either by experiment or by calculation and will differ for difierent solenoids, but the proper shape can easily be determined bymeasuring the resultant total pull on the solenoid and so shaping the cam that this resultant pull is kept uniform or substantially so. In order that the apparatus may be set to respond to different values of current, or different normal conditions of electric circuit, there is provided the adjusting screw and nut indicated at m by which the average pressure of the spring on the plunger may be varied.

By the combination of elements hereindescribed, it is possible to construct a regulator for trainlighting systems which will establish and maintain the desired conditions of regulations with variations of not more than three per cent. over the range of load variationfrom no lights, to the entire lighting system of the train or car, and with a variation of speed of the car from, say, twenty miles per hour, at which point the automatic switch Would be set to close the circuit of the generator, to ninety miles-per hour, which may be taken asthe maximum speed to be encountered 'in ordinary service.

What I claim is: a

"1. A direct' acting solenoid resistance regulator for train lighting systems, comprising a resistance divided into a sufiicient number of sections to prevent objectionable variations of current in the controlled circuit upon passing from one resistance section to the next, compactly arranged termi nals for the resistance sections, a contact a number of thin contact said resistance terminals and spring-pressed into close engagement therewith, a solenoid responsive to electrical variations in the circuit to be regulated and having a plunger operatively connected to the contact arm, and a dashpotfor damping the movement of the solenoid plunger.

2. A direct-acting solenoid resistance regulator for train lighting systems, comprising a resistance divided into a suflicient number of sections to prevent objectionable or substantially on,

plates making yielding rolling contact with said resistance terminals and spring-pressed into close engagement therewith, said plates belng normal to the surface of the, resistance terminals and being spaced apart andprovided with deformed portions'intermediate their ends permitting them to yield individually under the spring pressure, a

solenoid responsive to electrical variations in the circuit to be regulated and having a plunger operatively connected to the contact arm, and a dashpot for'damping the movement of the solenoid plunger.

3. A direct-acting solenoid resistance regulator for train lighting systems, coinpris ing a resistance divided into a sufiicient number of sections to prevent objectionable variations of current in the controlled circuit upon passing from'one resistance section to the next, compactly arranged terminals for the resistance sections, a contact arm made up of a numberof thin contact plates making yielding rolling contact Withsaid resistance terminals and spring-pressed into close engagement therewith, a solenoid responsive to electrical variations in the circuit to be regulated and having a plunger operatively connected to the contact arm, a dashpot for damping the movement of the solenoid plunger, and a spring arranged to resist the pull of the solenold with a force substantially proportional thereto throughout a wide range of movement of the plunger.

4. Adirect-acting solenoid resistance regs ulator for train lighting systems, comprising a resistance divided into a suflicient nuIn-' ber of sections to prevent ob ectionable riations of current in the controlled circuit upon passing from one resistance section to the next, compactly arranged terminals for the resistance sections, a contact arm made up, of a number of thin contact plates makin g yielding rolling contact with said resistance terminals and sp'ring pressed into close engagement therewith, a solenoid responsive of movement of the plunger, and means vfor adjusting the resisting force of the spring.

5. A direct-acting solenoid resistance regulator for train lighting systems, comprising a resistance divided into a sufficient number of sections to prevent objectionable,

variations of current in the controlled cir-' cuit upo'n passing from one resistance 'section to the next, compactly arranged terminals for the resistance sections, a contact arm made-up oi a number of thin contact plates making yielding rolling contact with arm, adashpot for damping tlr 1d resistance 't -;rminals and spring-pressed into close engagement therewith, said plates being normal to the surface or the resistance termlnals'and being spaced apart ant vided WItlIl-wd'GfOIIHGCl portions int their ends permitting them to yield g a c contact xo ement; thesolenoid plunger,--'and' a spring arnged :to resist the puli oi the solenoid th a force substantially proportional the circuit to be regulated and plungerop'eratlvely connected to etc throughout a Wide range of mcve' it er the plunger.

6. A direct-acting solenoid resistance regu ator fortrain lighting systems, comprisg a insistence divided into a sufiicient nu 'ib'er of sections to prevent objectionable .tions of current in. the controlled cirupon passing from one resistance secto the nextfcompactly] arranged termiqthe resistance, sections, a contact made up of a number of thin contact 'es making yielding rolling contact'with :ic. reel tance terminals and spring-pressed in o close engagement therewith, saidplates .g normal to the surface'or' the resistance male and being spaced apart and pro- 1' ends permitting them to yield individually under the spring pressure, a solenoid responsive to electrical variations in the circuit to be regulated andhaving a plunger opcratively connected to the contact arm, a dashpot for damping the movement of the solenoid. plunger a spring arranged to resist-the pull of the solenoid With a force substantially proportional thereto throughout a Wide: range of movement of the plun genand means for adjusting the resisting force of the spring, i 7. contact portion ffr contact arms of the character described, made up of a numher of thin metal plates held apart substan- 'tially normal to the surface to be contacted sure spring and deformed intermediate their contact edges and their bases, whereby they are adapted to yield individually under pressure.

8. The combination with a contact arm of the character described, of a stirrup depend ing therefrom approximately midway of the length of the contact portion and a presengaging the stirrup; substam tiallyas described. a

9. .The combination with aicontact arm- -ofi the character described. havinga contact portion made :up of a number o tthin metal ed with deformed portions intermediate contact pressure, substantially as d plates held apart substantially normal to,

forming the other contact'member and having a; contact portion composed of a plu- "rality of separated and flexible contact blades individually yielding and held. on the contact arm substantially normal to the contact. terminals the contact surface of one of saidme'mbers being curved, substantially as described.

11. In a regulator for electric train light mg systems, a resistance having a plurality of contact terminals and a contact arm can .rying a plurality of separated and flexible individually-yielding curved contact plates adapted to rock over said terminals, sub

. stantially as described.

12. In a regulator for electric train ingsystems, a resistance having a pl ot-contactterminals, a contact arm ca ing aplurality of separated and flexible 1U} dividually-yielding curved contact plates n adaptedto rock over sald terminals and spi'iiigocting on said arm to lllC' '2 the 1? Ina regulator for elect a lighting systems a solenoid having a plunger, a resistance, having a plurality of contact terminals, a contact arm 7 wa nd to be rocked on said terminals by the movement of said. plunger, and a spring acting in line with the axis of the plunger in opposition thereto and varying in stress coincidentally With the variation of tee magnetic pull.

14. In an electric train lighting system, a resistance having a plurality of rows of contact terminals, a resistance arm having a plurality of yielding curved contact portions electrically connected through conducting portions of the arm and adapted to collectively rock over and establish a short circuit between said rows of contact terminals and means acting on said arm to press it, toward said contacts and hold it against vibration;

. In testimony whe'reof I jailix my signature,

in presence of two witnessesl v PATRICK KENNEDY. Witnesses:

- MINERVA 'Lo nL, LE W. ROSENTHM'J. 

